May 1969 20-one (2) were prepared by the method of Karmas" and Mallory,12respectively. The oral progestational activity of these compounds was determined by the Claubsrg testla and the endometrial response was scored according to the index of M ~ P h a i 1 . l ~The McPhail index for gar-methyl-17aacetoxyprogesterone and compounds 5 was found to be +3.0 and 3.3.2, respectively, a t 0.5 mg. These data, though limited in nature, do point out that the oxygen function a t C-3 is not an absolute necessity for progestational response. On the other hand the McPhail index of 6a,l6a-dimethylprogesteroneand the oxime of 6 (2.1 and 0, respectively, a t 5.0 mg) points out the importance of the C-20 functional group for protein binding. The polarity of the carbonyl group constitutes a point of contact with the receptor superior to that of the oxime. The oxidation-reduction of the oxygen function a t C-3 as a possible factor in the mechanism of action probably can be ruled out.
NOTES
549
2-Hy droxy -Z-phenylethylhydrazine Monoamine Oxidase Inhibitors CHARLES F. BIRFKNECHT,GERILD PIRCH,'
Dzvzsaon of lledzcznal Chemzstry, College of Pharmacy, The rnzverszty of Zowa, Zowa Czty, Zowa 62240
WILLILVhI. McIsiac,
IAD
BENGT. Ho
Texas Research Znstatute of -1lenlal Scaences, Texas lledzcal Center, Houston, Texas 77025 Receaved October 21, 1.968
2-Hydroxy-2-phenylethylhydrazine (1) was synthesized first by Benoit2 and observed to have typical sympathomimetic activity with a potency l/bOfith that of epinephrine.3 Later, Biel, et uL14 evaluated 1 for monoamine oxidase (MAO) inhibitory activity and found it to be eight times as potent as iproniazid in wivo, but inactive a t 10-5 ill in vitro. In this study we desired to Experimental Section determine the effect of position and number of car$11 melting points were taken with a Fisher-Johns melting bethoxy groups 011 M A 0 inhibitory activity and to point apparatus and are uncorrected. The uv and ir data were verify the lack of in vitro activity of 1. obtained on a Cary Mode 111 and Beckman IR-5 spectrophotomThe Wcarbethoxy derivative (2) was prepared by eters, respectively. S m r spectra were determined on a Varian treating l2with ethyl chloroformate. The first approach '4-60 spectrometer in CDCla using TMS as an internal standard. to the synthesis of the S2-carbethoxy derivative (3) Elemental analyses were performed by Midwest Microlab Inc., Indianapolis, Ind. Khere analyses are indicated only by symbols involved the reaction of styrene oxide and ethyl of the elements, analytical results obtained for those elements carbazate. This procedure led to a complex mixture of were within *0.4y0 of the theoretical values. products, a situation not unexpected in light of the mix17~-Acetoxy-6-methylpregn-3,5-dien-20-one (3).-Raney Ni ture obtained by treating styrene oxide with ethyl (88.0 g ) was suspended in 800 ml of hIe2CO and refluxed with stirring under S p for 0.5 hr. The mixture was cooled to room gly~inate.~ temperature and t o it was added 8.0 g of 1 in 100 ml of THF. Compound 3 was synthesized by treating styrene Stirring was continued at 25" for 2.5 hr. The reaction mixture bromohydrin with ethyl carbazate. The Ni,N2-diwas filtered and the filtrate was evaporated to give an oil. carbethoxy derivative (4) mas prepared from either Recrystallization from ether-hexane yielded 4.5 g (70%) of 3: mp 132-133'; "::A 241 mp; :::A 1650, 1720, 1731 cm-l; 2 or 3 by reaction with ethyl chloroformate. That the nmr, multiplets at 5.68 and 6.41 ppm (C-3, C-4). Anal. ( C2rHsaOo) positions of the carbethoxy groups are correctly assigned C, H. to nitrogens and are not on the alcoholic oxygens is 17a-Acetoxy-6-methylpregn-5-en-20-one (5).-Compound 3 shown by the ir absorption of the carbonyl groups of (1.0 g) was dissolved in 15 ml of ilcOH and 700 mg of 57" Pd-C 2, 3, and 4. The carbonyls of ethyl carbazate and was added. The mixture was hydrogenated a t room temperature until 1 equiv of Ha was consumed. It was filtered and the diethyl carbonate are a t 1716 and 1750 cm-', respecfiltrate was evaporated to give an oil. Repeated recrystallization tively. Compounds 2, 3, and 4 are a t 1690, 1715, and from hexane gave 250 mg ( 3 6 ' 3 ) of 5: mp 166-168"; A ~ ~ ~ h e x s n e 1725 and 1705 cm-l, respectively. Attempts to cause 198 mg ( e 8900);:,"A 1723, 1737 cm-l; nmr, no resonance due to r\'--t 0 migration of the carbethoxy group according to vinyl protons. Anal. (C24H3603)C, H. 6,16a-Dimethylpregn-3,5-dien-20-one (4).--h mixture of 80 g the method of Lyle and Durandc failed. of Raney S i in 700 ml of Me2CO was stirred and refluxed for Biological Results.---Mitochondrial moiioamine oxiC 5 hr under Sa. The mixture was cooled to room temperature dase from beef liver was isolated and purified as deand to it was added a solution of 6.9 g of 2 in 75 ml of THF. scribed by Ho, et al.' Incubation v a s carried out a t Stirring was continued for 3.5 hr at 25". The mixture was 37" for 30 min in a solution containing 0.15 mpmole of filtered and the filtrate was evaporated t o a dark residue. Chromatographic separation on neutral alumina gave 3.9 g (80%) of 4 substrate, tyramine-l-C14, per milliliter, varying amounts on elution with 9:l hexane-EtzO. Recrystallization from hexane of inhibitor, 20 p1 of enzyme, phosphate buffer pH 7.4, ::"A 241 mg; gave analytically pure sample: mp 125-126"; KBr and water to make a final volume of 1 ml. The product, A,, 1650, 1705 em-'; nmr, 5.30 ppm (vinyl multiplets). Anal. a mixture of p-hydroxyphenylacetaldehyde and p-hy(Cn~Hsao):C, H. 6,16~-Dimethylpregn-5-en-20-one (6).-Compound 4 (500 mg) droxyphenylacetic acid, was extracted with EtOAc in was dissolved in 15 ml of AcOH and to it was added 250 mg of 5% strongly acidic medium. After removal of solvent, the Pd-C. The mixture was hydrogenated at room temperature until product was assayed for C1* in a liquid scintillation The mixture was filtered and the 1 equiv of H p was consumed. spectrometer and the concentration of the inhibitor a t filtrate was evaporated to give an oil which failed to crystallize; Au"cl m.r 1705 cm-I; nmr, no resonance due to vinyl protons. which enzyme activity was 50"/;, inhibited (I50) was deAnalyzed as oxime, mp 75-76". Anal. (CzaHa~X0)C, H , 1;. termined. The results are shown in Table I. Acknowledgment.- I wish to express my apprcciatioii (1) National Science Foundation undergraduate research participant. to Dr. R. P. Blye for the biological data and to Dr. (2) G. Benoit, Bull. SOC.Chim. France, 6 , 708, (1939). I. Scheer for his valuable suggestions in the preparation (3) G. Benoit and D. Bovet, Compt. Rend. SOC.B i d . , 136, 356 (1942). (4) J. H. Biel, A. E . Drukker, T. F. Mitchell, E. P. Sprengeler, P. A. Nuhfer, of this manuscript. A . C. Conway, and A. Horita, J . A m . Cnem. Soc., 81, 2805 (1959). (11) (12) (13) (14)
G Karmas, Tetrahedron Letters, 1093 (1964) R. Mallory, personal communications. C. Clauberg. Zentr. Gynaekol., 54, 2757 (1930). AI. K. McPhail, J. Physiol. (London), 83, 145 (1936).
( 5 ) K. Jankowski and C. Berse, Can. J. Chem., 44, 1513 (1966). ( 6 ) G. G. Lyle and hi. L. Durand, J . O w . Chem., 32, 3295 (1967). (7) B. T. Ho, IT. 11.RIcIsaac, K. E. Kalker, and V. Estever, J. Pharm. Sei.,
57, 269 (1968).
550
\-01. 12
rr \BLE
I
A1.10 R l CbH,CHOHCHySHI!:
INHIBITION O F
I
It1 Kl
t omprl
1 . t : u t rat e 2 .HCl
3.IICI 4.tICl
H COLC2Hj H COiCIH,
Isa, mJf
I< 2
H €I COiCJT
j
CO~CIH~
0.16 7.8 5.4 16.0
Discussion.-The potency order of 1 > 3 > 2 > 4 is coiisisteiit xith accepted structure-activity relatioiiships for X A O iiihibitioii in phenylethylhydraziiie nmlclcules.b The preseiice of' a carbethoxy group oil either 9 adversely affects the in vitro AIAO inhibitory potency. The discrepancy betweeii tlie in vitro activity of 1 observed in this study aiid the results of Biel, et al.,? may be due to the use of tliffereiit substrates. Experimental Section9
derivatives pronipted us to syithesize mid t t k s t for hypoglycemic effects :I group of related coiigeiiers i i i which the carboxyl group was rqdaced hy an aritlir, nzolyl moiety.? It W : L ~ :uiticipat totrazole ~ w u l dimpart tlie saiii~dcgree c the resultiiig txmipouiids ns tlw carlioxyl group 1 ) I ~ would iiot# uiidergo the facilc dccarhxylatioii typicxl for p-sulfiiiyt- a i d /3-sulfonj-lacctic :tcids iTahk I). A wrieb of :~lkyl-, aralkyl- :tiitl arylthioac.ctoi~itriler (Tablc II), prcpared by alky1:itioii of tlit. r(quihitc1 rncrcaptaii with rliloroacrtoiiitrile, wi$ coiivrrtetl to tlic, correspoiicliiig trtr:izoles usiiig tlie iiiethocl of Fitiiiegaii, el aL4 ( )siclatioil of the rcsulting t hioniethyltct razoles using H202111 .IcOH providetl :iroutc t o t h . clcsirctl sulfo11es. Titratioii 111 1:1 dioxane watw slion-et1 the tliiuinethyltetrazoles to be weak acids; the sulfoiiylnir~thyl (wigciiers, because of the inductive effect of the sulfont. group, were soiiien hat inore acidic, cliff eriiig from thc sulfitlcs by ~iiorcthan 1 pK., uiiit. Compound 2 gave ail it1101ii~loustitration curve n-hich was iiidicativc of LL dibahic acid with :t neutralization cyuivalcnt approslmatrlj' one-half t hc calculated value. It is probahlc that the CH, group, flanked by the CF, and YO. iiioirties, i h d T i c k t l y acidic to be titrated doiig with the tetruzolc. The nbseiice of :L clisceiiiilrlc. doublc~ break iii thi, titration curye preveiited rucaniiigfiil ralrulatioii of pK,, aiitl pKa . Soiic of tlie conipouiitls slio~vedany hypoglyceiiiic :tctivity \I-lieii sci*rceiictl :tccordiiig to previously tlesciribed procedures.
2-Hydroxy-2-phenylethylhydrazine (l).--The method of Benoit2 was employed. The oxalate salt, mp 170" [;lnal. (CioHlLizOj) C, H, SI,and the tartrate salt, mp 141-143", n-ere recrystallized from AIeOH-Et20. N~-Carbethoxy(2-hydroxy-2-phenyl)ethylhydrazine( 2 ) was synthesized by treating 1 with ethyl chloroformate as descrihed lo The HC1 salt was recrystallized from CHC13, mp 134-136 '. -trial. (CllH,iClS20,)C, H, N. 2-liydroxy-2-phenyl)ethylhydrazine (3).-To a solution of styrene bromohydrin (2.42 g, 0.012 mole) in 100 ml of EtOH was added a solution of ethyl carbazate (1.4 g, 0.0133 mole) in 50 ml of EtOH. The solution mis refluxed overnight, evaporated under reduced pressure, and treitted with 20 ml of IO?:, SaHCO3 solution and 200 ml of KtOH. The precipitate was removed and the solution was evaporated to yield 3 as an oil, Experimental SectionG yield 70(,'1). The oxalate, mp 112-115" [ A n a l . ( C I ~ H ~ I N ? ~ ; ) 5-(2,2,2-Trifluoroethylthiomethyl)tetrazole.-.~ mixture oi 8.1 g C, H, SI,and the €IC1 salt, nip 105--ltOc, were recrj-stallized (0.02 mole) of 3,2,2-trifluoroet,hylthioacetonitrile,'2.16 g (0.04 from LIeOH-EtyO. Nl,N2-Dicarbethoxy( 2-hydroxyl-2-pheny1)ethylhydrazine (4).--- mole) of SHICI, 2.8 g (0.044 mole) of SaSa, and 0.02 g of IiC1 in 15 ml of DNF was heated a t steam-bath temperatures overnight.. To :t cold solution of 2 (4.0 g, 0.018 mole) in 150 ml of Et20 was The reaction mixture was cooled, diluted with 30 ml of 1.120, and d ethyl chloroformate (2.95 g. 0.027 mole) in 100 ml of acidified with concentrated HCI to p H 3-4. The precipitated . After stirring for 2 hr t h e product (4)was removed by solid was filtered and dried, 2.5 g. tion. The HC1 salt, mp 142-143 ', j-ield 65!;, was recrystalThe thiomethyltetraxoles were prepared by a similar procedure lixcd from CHCl3-lCtOhc. - 3 n d . iCi,H,lCIS,O:) C , H: N. in yields of 60-90%; they are listed with their physical properties Acknowledgments.--~-Tliecscelleiit tcchiiical assistin Table I. 5-(Isopropylsulfony1methyl)tetrazole.-To a svlutioii oi 1 1 .\ K ance of X r . E t l m d Fritcliie is aclinowledgetl 11y (0.075 mole) of j(isopropylthiomethyl)tetra~[ilein 75 nil i d ' IT.11. I. ant1 E. T. H. Thir project was supported iii glacial AcOH was : d i e d 19 g of 30''; H202dropwise ovrr :i pttrt by Graiit, MH-OS737 froin t,he Satioiial Institute period of 15 min. The reaction mixture was stirred at room of Mental Health m i l (iraiit GY-2352 from the Xationd temperature overnight, and was then heat,ed a t steam-hi h tcrnperatwe for 15 min. The solution was cooled, anti 1 tic, protinct Science Found-'1 t '1011. ' precipitated by the addition of pentane. ( 8 ) 13. 11. Blooin, .iiui. N . k'. Scad. Sei., 107, 878 (1963). in Table I were all prepared I)>- a 3iniil:ir (!I) Melting points were determined on a Hoover apparatus and are uncorrrcted. \There analy$es are indicated by symbols of the elements, analytical r e ~ i l l t sobtained for those elements were within *0.4y0 of the theoretical v:illlc!s. hein. Reo., 64,645 (1964). 1 IO) 11.X x t z n r r , R . 1'. Iiurkjy, ani1 R.S.C'ott
p-Chlorophenylthioacetonitri1e.-To a suspension of 59 g (0.42 mole) of p-chli)rothiophenol and 55 g (0.42 mole) of &COS in 275 ml of 1,2-diniet,hoxyethane was added, dropwise, 32 g (0.42 mole) of chloroacetonitrile. The resulting mixture was stirred for 1 hr, and was then refluxed overnight. Moat of the solvent was removed under reduced pressure followed by the addition of
Thiomethyltetrazole Hypoglycemic Agents S. Graff, Ed., Joliii \Vilt>y: i n ~ l
A report' of the potentiation of insulin hypoglycemia by a series of pheiiylsulfiiiyl- a i d -sulfonylacetic acid (1)
E. H ~ e \ z .
\Volf, aiid H dlvarrz. Hull. Soc. Chtm. France, 1027 (1Y6J).
(3) J. S. Mihina and It. A l . Herbst, J. O r p . Chem.. 15, 1082 (lO.>O). (4) W.G. Finnegaii, K . A . Henry, and R. Lofquirt, J . .Im. Chem. SOC.,80. 3908 (1958). (5) J. AI. AIc.\lanus, J . \f-. AIcFarland, C . F. Gerber, W.AI. McLamore, iind G, D. Laubnch. J . M e d . f'hm,, 8, 766 (1985). (6) AIelting points u-['re determined on a Thomas-Hoover capillary nicltinp point apparatw and *re corrected. The analyses were carried out by the Physical LIeasurementu I ~ h o r a t o r yof Chas. Pfizer & Co., Inc. Titrations were done in 1 :1 (V!SJ diomne-water using a hletrohm potentiograph AIodel E430. iThere analyses a r e indicated only by symbols of elements, analytical results obtained for those elrmrnts were within *O.4y0of the theoretical values. (7) J. AI. SIcAlanus, J . ffieferocycl. Chem., 5, 137 (1968).
